I'm reviewing general chemistry and I'm having problems with one of the questions in the book.

A sample of vermilion-colored mineral was weighed in air, then weighed again while suspended in water. An object is buoyed up by the mass of the fluid displaced by the object. In air, the mineral weighed 18.49 g; in water, it weighed 16.21 g. The densities of air and water are 1.205g/L and 0.9982g/cm^3, respectively. What is the density of the mineral?

The answer is 8.10g/cm^3.

Please help! This is probably pretty easy and I'm not getting it. Please show the steps to getting this answer, and explain them.

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Jackass.

I just don't know how to do the problem. It would be nice for someone to show me. I'm having a hard time finding out how to do it.

so we know the mass of the object, 18.49 g.

now we need to find it's volume. the method we have is by suspending it in water, where it's weight is reduced by the weight of water it displaces.

it's displacement is 2.28 g (18.49 - 16.21). im going as assume water has a density of 1, but you would have to find out the volume of water displaced.

so we have a 2.28 cm^3 object that weighs 18.49 g, giving a density of 8.109 g.

Well shit, that was easy. Thanks a lot!